Wednesday’s hearing, the third of its kind, focused on an organization which has been recruiting American citizens of Somali descent in the Minneapolis-St. Paul area, according to King.

The chairman of the House Homeland Security Committee says more than 40 Americans have been recruited by a group known as al-Shabab and have gone to fight in Somalia. King said at least 15 Americans and three Canadians are believed to have been killed.

Al-Shabab claimed responsibility for the double suicide bomb attack in Uganda’s capital last year and members have aligned themselves with other anti-Western terror groups.

“Al-Shabab is now linking up with al-Qaida and they’re training together, working together and the threat is that they would be coming back to attack the United States,” said King. “This isn’t just me saying this. This is pretty uniform view of the intelligence community based on what they say in public. I’m not even getting into what they say privately.”

United States citizens may be particularly attractive as recruits to foreign terror groups because of their comparative ease of access to the U.S. homeland.

King has been criticized for unfairly singling out Muslims in his series of hearings over the past few months on Islamic radicalization in the U.S. Some of those who oppose these inquisitions have said the committee should also focus on the threat other types of extremism, including right-wing extremism in the U.S., particularly as that ideology appeared to motivate the man accused in the recent deadly attacks in Norway.

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